diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cf6a3c7e..99ff50fa 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,8 +36,12 @@ jobs:
       - name: Install dependencies
         run: composer update --${{ matrix.stability }} --prefer-dist --no-interaction --no-suggest
 
+      - name: PHP Security Checker
+        uses: symfonycorp/security-checker-action@v2
+        if: ${{ matrix.stability == 'prefer-stable' }}
+
       - name: Execute tests
         run: vendor/bin/phpunit --coverage-clover=coverage.clover --verbose
 
       - name: Upload Code Coverage
-        run: wget https://scrutinizer-ci.com/ocular.phar && php ocular.phar code-coverage:upload --format=php-clover coverage.clover
\ No newline at end of file
+        run: wget https://scrutinizer-ci.com/ocular.phar && php ocular.phar code-coverage:upload --format=php-clover coverage.clover
diff --git a/src/Api/Client.php b/src/Api/Client.php
index eacd11ca..1681836b 100644
--- a/src/Api/Client.php
+++ b/src/Api/Client.php
@@ -224,12 +224,10 @@ public function buildAuth()
      */
     public function buildOptions(array $options = [])
     {
-        return array_merge_recursive(
-            $options,
-            [
-                'headers' => $this->getHeaders(),
-            ]
-        );
+        return [
+            'body'    => json_encode($options ?? []),
+            'headers' => $this->getHeaders(),
+        ];
     }
 
     /**
@@ -340,7 +338,7 @@ public function getPassword()
      *
      * @return string
      */
-    public function getUrl($path = null)
+    public function getUrl($path = '')
     {
         return $this->url . '/v4_6_release/apis/3.0/' . ltrim($path, '/');
     }
@@ -395,7 +393,7 @@ protected function isCollection(array $array)
      */
     protected function isLastPage(ResponseInterface $response)
     {
-        return !(bool)preg_match('/rel="last"$/u', $response->getHeader('Link')[0] ?? null);
+        return !(bool)preg_match('/rel="last"$/u', $response->getHeader('Link')[0] ?? '');
     }
 
     /**
diff --git a/tests/Api/ClientTest.php b/tests/Api/ClientTest.php
index 15eec3a1..f747f7ae 100644
--- a/tests/Api/ClientTest.php
+++ b/tests/Api/ClientTest.php
@@ -294,7 +294,7 @@ public function it_builds_the_expected_options_array()
         $this->client->setIntegrator($username);
 
         $options = [
-            'extra'   => 'option',
+            'body'    => json_encode(['extra' => 'option']),
             'headers' => [
                 'added'         => 'header',
                 'Accept'        => 'application/vnd.connectwise.com+json; version=2019.5',